feat: add easter egg - triple-tap settings title opens fiatcode.dev

- Add url_launcher dependency
- Add Android queries element for https scheme visibility
- Add triple-tap detection on Settings AppBar title
- Simplify to direct URL launch (no animation)

lib/main.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
+
 import 'main_screen.dart';
 import 'permission_screen.dart';
 import 'preferences.dart';

lib/settings_screen.dart

@@ -19,7 +19,7 @@ class _SettingsScreenState extends State<SettingsScreen> {
   late TextEditingController _heartbeatController;
   late int _accuracy;
   late bool _offlineBuffer;
-  late   bool _stopDetection;
+  late bool _stopDetection;
   int _tapCount = 0;
   DateTime? _lastTapTime;